1. Field of the Invention
The present invention relates generally to a metal living hinge mechanism. More particularly, the invention relates to a metal living hinge formed of sheet metal and which may be used through a preselected angular range for some minimum number of cycles without failure due to bending stress.
2. Description of the Related Art
Various devices utilize sheet metal components. Many of these components require repeatable access by opening, and therefore utilize a hinge. However, multi-piece hinge mechanisms are costly, and more difficult to incorporate in the manufacturing process. In the lighting industry, there is a multitude of fixture types, including for instance, troffer lighting, recessed lighting, outdoor landscaping, and in-cove lighting. In the various lighting fixtures, it is desirable to utilize a junction box or ballast housing which has a pivoting door assembly. These structures generally require limited access to internal components during installation and for occasional maintenance issues.
With respect to in-cove luminaires, these fixtures have a certain unique problem as related to height and serviceability of the devices. Architects generally utilize the smallest cove allowable to conceal the fixture, which imposes limitations on the height and depth of the fixture. This generally limits the ability to install reflectors and larger ballasts.
Maintenance issues are also a design factor which must be accommodated. Lamp replacement in-cove lighting may be at heights of twenty or more feet above ground level. Ballasts must also be accessible, as they typically need replacement after several years of continuous use. During the typical life of a fixture, ballasts may need to be replaced five to seven times. Since many of these fixtures are formed of stamped metal, doors must be removably formed. A hinge detail would be preferable to provide access to the ballast area of the fixture without necessitating removal of a door. For example, a living hinge assembly would be desirable, however such living hinge must be able to withstand a certain minimum number of cycles in order to allow for lamp changes and/or ballast replacements. Heretofore, such living hinge has not been available.
Given the foregoing, it will be appreciated that a metal living hinge assembly is needed which may be formed of sheet metal and allows repeated use through a preselected angular range of motion and number of cycles before failure. The living hinge of the instant disclosure may be utilized with various types of devices, including but not limited to luminaires.